/*
 * Copyright (c) 2012-2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
// $Id: XPathFactoryImpl.java,v 1.2 2005/08/16 22:41:13 jeffsuttor Exp $

package com.sun.org.apache.xpath.internal.jaxp;

import com.sun.org.apache.xalan.internal.XalanConstants;
import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
import com.sun.org.apache.xalan.internal.res.XSLMessages;
import com.sun.org.apache.xalan.internal.utils.FeatureManager;
import com.sun.org.apache.xalan.internal.utils.FeaturePropertyBase;

import javax.xml.XMLConstants;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathFactoryConfigurationException;
import javax.xml.xpath.XPathFunctionResolver;
import javax.xml.xpath.XPathVariableResolver;

/**
 * The XPathFactory builds XPaths.
 *
 * @version $Revision: 1.11 $
 * @author  Ramesh Mandava
 */
public class XPathFactoryImpl extends XPathFactory {

    /**
     * <p>Name of class as a constant to use for debugging.</p>
     */
    private static final String CLASS_NAME = "XPathFactoryImpl";

    /**
     *<p>XPathFunctionResolver for this XPathFactory and created XPaths.</p>
     */
    private XPathFunctionResolver xPathFunctionResolver = null;

    /**
     * <p>XPathVariableResolver for this XPathFactory and created XPaths</p>
     */
    private XPathVariableResolver xPathVariableResolver = null;

    /**
     * <p>State of secure processing feature.</p>
     */
    private boolean _isNotSecureProcessing = true;
    /**
     * <p>State of secure mode.</p>
     */
    private boolean _isSecureMode = false;
    /**
     * javax.xml.xpath.XPathFactory implementation.
     */

    private boolean _useServicesMechanism = true;

    private final FeatureManager _featureManager;

    public XPathFactoryImpl() {
        this(true);
    }

    public static XPathFactory newXPathFactoryNoServiceLoader() {
        return new XPathFactoryImpl(false);
    }

    public XPathFactoryImpl(boolean useServicesMechanism) {
        _featureManager = new FeatureManager();
        if (System.getSecurityManager() != null) {
            _isSecureMode = true;
            _isNotSecureProcessing = false;
            _featureManager.setValue(FeatureManager.Feature.ORACLE_ENABLE_EXTENSION_FUNCTION, FeaturePropertyBase.State.FSP, XalanConstants.FEATURE_FALSE);
        }
        this._useServicesMechanism = useServicesMechanism;
    }

    /**
     * <p>Is specified object model supported by this
     * <code>XPathFactory</code>?</p>
     *
     * @param objectModel Specifies the object model which the returned
     * <code>XPathFactory</code> will understand.
     *
     * @return <code>true</code> if <code>XPathFactory</code> supports
     * <code>objectModel</code>, else <code>false</code>.
     *
     * @throws NullPointerException If <code>objectModel</code> is <code>null</code>.
     * @throws IllegalArgumentException If <code>objectModel.length() == 0</code>.
     */
    public boolean isObjectModelSupported(String objectModel) {

        if (objectModel == null) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_OBJECT_MODEL_NULL, new Object[] { this.getClass().getName() });

            throw new NullPointerException(fmsg);
        }

        if (objectModel.length() == 0) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_OBJECT_MODEL_EMPTY, new Object[] { this.getClass().getName() });
            throw new IllegalArgumentException(fmsg);
        }

        // know how to support default object model, W3C DOM
        if (objectModel.equals(XPathFactory.DEFAULT_OBJECT_MODEL_URI)) {
            return true;
        }

        // don't know how to support anything else
        return false;
    }

    /**
     * <p>Returns a new <code>XPath</code> object using the underlying
     * object model determined when the factory was instantiated.</p>
     *
     * @return New <code>XPath</code>
     */
    public javax.xml.xpath.XPath newXPath() {
        return new com.sun.org.apache.xpath.internal.jaxp.XPathImpl(xPathVariableResolver, xPathFunctionResolver, !_isNotSecureProcessing, _useServicesMechanism, _featureManager);
    }

    /**
     * <p>Set a feature for this <code>XPathFactory</code> and
     * <code>XPath</code>s created by this factory.</p>
     *
     * <p>
     * Feature names are fully qualified {@link java.net.URI}s.
     * Implementations may define their own features.
     * An {@link XPathFactoryConfigurationException} is thrown if this
     * <code>XPathFactory</code> or the <code>XPath</code>s
     *  it creates cannot support the feature.
     * It is possible for an <code>XPathFactory</code> to expose a feature
     * value but be unable to change its state.
     * </p>
     *
     * <p>See {@link javax.xml.xpath.XPathFactory} for full documentation
     * of specific features.</p>
     *
     * @param name Feature name.
     * @param value Is feature state <code>true</code> or <code>false</code>.
     *
     * @throws XPathFactoryConfigurationException if this
     * <code>XPathFactory</code> or the <code>XPath</code>s
     *   it creates cannot support this feature.
     * @throws NullPointerException if <code>name</code> is
     * <code>null</code>.
     */
    public void setFeature(String name, boolean value) throws XPathFactoryConfigurationException {

        // feature name cannot be null
        if (name == null) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_FEATURE_NAME_NULL, new Object[] { CLASS_NAME, new Boolean(value) });
            throw new NullPointerException(fmsg);
        }

        // secure processing?
        if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
            if ((_isSecureMode) && (!value)) {
                String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_SECUREPROCESSING_FEATURE, new Object[] { name, CLASS_NAME, new Boolean(value) });
                throw new XPathFactoryConfigurationException(fmsg);
            }

            _isNotSecureProcessing = !value;
            if (value && _featureManager != null) {
                _featureManager.setValue(FeatureManager.Feature.ORACLE_ENABLE_EXTENSION_FUNCTION, FeaturePropertyBase.State.FSP, XalanConstants.FEATURE_FALSE);
            }

            // all done processing feature
            return;
        }
        if (name.equals(XalanConstants.ORACLE_FEATURE_SERVICE_MECHANISM)) {
            //in secure mode, let _useServicesMechanism be determined by the constructor
            if (!_isSecureMode)
                _useServicesMechanism = value;
            return;
        }

        if (_featureManager != null && _featureManager.setValue(name, FeaturePropertyBase.State.APIPROPERTY, value)) {
            return;
        }

        // unknown feature
        String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_FEATURE_UNKNOWN, new Object[] { name, CLASS_NAME, new Boolean(value) });
        throw new XPathFactoryConfigurationException(fmsg);
    }

    /**
     * <p>Get the state of the named feature.</p>
     *
     * <p>
     * Feature names are fully qualified {@link java.net.URI}s.
     * Implementations may define their own features.
     * An {@link XPathFactoryConfigurationException} is thrown if this
     * <code>XPathFactory</code> or the <code>XPath</code>s
     * it creates cannot support the feature.
     * It is possible for an <code>XPathFactory</code> to expose a feature
     * value but be unable to change its state.
     * </p>
     *
     * @param name Feature name.
     *
     * @return State of the named feature.
     *
     * @throws XPathFactoryConfigurationException if this
     * <code>XPathFactory</code> or the <code>XPath</code>s
     *   it creates cannot support this feature.
     * @throws NullPointerException if <code>name</code> is
     * <code>null</code>.
     */
    public boolean getFeature(String name) throws XPathFactoryConfigurationException {

        // feature name cannot be null
        if (name == null) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_GETTING_NULL_FEATURE, new Object[] { CLASS_NAME });
            throw new NullPointerException(fmsg);
        }

        // secure processing?
        if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
            return !_isNotSecureProcessing;
        }
        if (name.equals(XalanConstants.ORACLE_FEATURE_SERVICE_MECHANISM)) {
            return _useServicesMechanism;
        }

        /** Check to see if the property is managed by the security manager **/
        String propertyValue = (_featureManager != null) ? _featureManager.getValueAsString(name) : null;
        if (propertyValue != null) {
            return _featureManager.isFeatureEnabled(name);
        }

        // unknown feature
        String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_GETTING_UNKNOWN_FEATURE, new Object[] { name, CLASS_NAME });

        throw new XPathFactoryConfigurationException(fmsg);
    }

    /**
     * <p>Establish a default function resolver.</p>
     *
     * <p>Any <code>XPath</code> objects constructed from this factory will use
     * the specified resolver by default.</p>
     *
     * <p>A <code>NullPointerException</code> is thrown if
     * <code>resolver</code> is <code>null</code>.</p>
     *
     * @param resolver XPath function resolver.
     *
     * @throws NullPointerException If <code>resolver</code> is
     * <code>null</code>.
     */
    public void setXPathFunctionResolver(XPathFunctionResolver resolver) {

        // resolver cannot be null
        if (resolver == null) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_NULL_XPATH_FUNCTION_RESOLVER, new Object[] { CLASS_NAME });
            throw new NullPointerException(fmsg);
        }

        xPathFunctionResolver = resolver;
    }

    /**
     * <p>Establish a default variable resolver.</p>
     *
     * <p>Any <code>XPath</code> objects constructed from this factory will use
     * the specified resolver by default.</p>
     *
     * <p>A <code>NullPointerException</code> is thrown if <code>resolver</code> is <code>null</code>.</p>
     *
     * @param resolver Variable resolver.
     *
     *  @throws NullPointerException If <code>resolver</code> is
     * <code>null</code>.
     */
    public void setXPathVariableResolver(XPathVariableResolver resolver) {

        // resolver cannot be null
        if (resolver == null) {
            String fmsg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_NULL_XPATH_VARIABLE_RESOLVER, new Object[] { CLASS_NAME });
            throw new NullPointerException(fmsg);
        }

        xPathVariableResolver = resolver;
    }
}
